The Heermann Gull 
Its breeding haunts, known to include certain islands off the coast of 
Lower California and western Mexico, have only recently come to light, 
and are not yet very fully mapped out. The largest colony yet described 
is that of Ildefonso Island in the Gull of California, in Latitude 26° 
38' north, where, in 1909, W. W. Brown, Jr., estimated that 2500 pairs 
were nesting. Nesting takes place in March and early April, so that by 
the last week in May returning migrants, having completed the duties 
of reproduction, begin to appear along the coast of southern California. 
There is a steady increase in numbers till July, at which time, and after, 
this species outnumbers the native Westerns (Lams occidentalis) two to 
one in southern waters. The migratory movement persists throughout 
the summer and carries many of the species as far north as British Co¬ 
lumbia; but in general it may be affirmed that they are present in a stead¬ 
ily decreasing ratio anywhere north of Monterey. Heermann Gulls 
are a little clannish, and are likely to flock by themselves even when 
sharing their resting places with other species. Their relations with the 
Western Gull, however, are most familiar, and they are to be found pretty 
much wherever occidentalis goes, save that they will not go far inshore nor 
under any circumstances venture “cross lots” to visit interior waters. 
By the end of January adult birds have assumed white heads, which 
mark the breeding plumage, and have begun to forsake Californian waters. 
Yet there always remain behind a sufficient number of stragglers, imma- 
tures and non-breeding birds, to 
disguise the fact that Blasipus heer¬ 
mann i is really an extra-limital 
breeder. 
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Taken at Redondo Beach 
A TROPHY 
Photo by the Author 
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